Established rules and routines help children get age-appropriate sleep amounts, according to the 2014 National Sleep Foundation’s “Sleep in the Modern Family” Poll, released Jan. 26.

While most parents endorsed the idea of the importance of sleep, 90 percent of children did not sleep the full amount of time recommended for their age group, researchers found.

Consequences of poor sleep among children and adolescents include behavioral problems, impaired learning and school performance, sports injuries, problems with mood and emotional swings and a worsening of health-related issues, including obesity, researchers found.

Evidence also indicates adolescents’ lack of sleep could be associated with substance abuse, suicidal behaviors and driving while drowsy.

The poll’s prime objective was to get a picture of sleep in families with at least one school-age child.

Researchers from Penn State, Case Western Reserve University, the University of Chicago and others evaluated U.S. households with children aged 6 to 17 years old using Internet-based interviews. More than 1,100 parents or guardians, average age 42, participated.

“We were interested in parental perception of the importance of sleep duration and sleep quality, habits, and routines of the families and children, and obstacles preventing adequate sleep,” Penn State associate professor Orfeu Buxton said in a special release.

Sufficient sleep duration is conservatively estimated to be at least nine hours a night for ages 6-11 and at least eight hours for ages 12-17, researchers say.

Significant predictors of adequate sleep duration were found to be regular sleep-wake routines, consistent enforcement of rules about caffeine, keeping technology off in their bedrooms overnight and parents’ education.

“Reducing the encroachment of technology and media into sleep time and supporting well-known sleep hygiene principles should be a focus of public health intervention goals for sleep health,” the release said.

“We have previously demonstrated the negative effect that use of light-emitting technology before bedtime can have on sleep, and now in this study we see how parental rules and routines regarding technology can influence the quantity and quality of their children’s sleep,” said Anne-Marie Chang, assistant professor of bio-behavioral health at Penn State and co-author of the study.

Chang and colleagues recently demonstrated that reading on an iPad before bedtime, compared with reading a print book, can impair sleep, delay circadian timing and make children less alert the following morning.

Other factors contributing to poor sleep, researchers said, complicated and hectic daily schedules with competing work, school, social and recreational activities. Neighborhood noise also plays a role in disrupting sleep.

Electa Draper is the health writer for The Denver Post and has covered every news beat in a 22-year journalism career at three newspapers. She has a bachelor's degree in biology and a master's in journalism.